code: def _add_parent_nodes_to_graph(
      causal_graph: nx.DiGraph, parent_nodes: list, node_name: str
  ) -> None:
      for parent_node in parent_nodes:
          causal_graph.add_edge(parent_node, node_name)
  
imports: import ast
  import logging
  import re
  from typing import Tuple
  import networkx
  import numpy
  import scipy.stats
  from dowhy.gcm import AdditiveNoiseModel, EmpiricalDistribution, ScipyDistribution, StructuralCausalModel
  from dowhy.gcm.causal_mechanisms import StochasticModel
  from dowhy.gcm.causal_models import PARENTS_DURING_FIT
  from dowhy.gcm.ml.prediction_model import PredictionModel
  from dowhy.gcm.util.general import shape_into_2d
  from dowhy.graph import get_ordered_predecessors
label_desc: Use image node_id 3 for calling a global function with example usage: _add_parent_nodes_to_graph(causal_graph, parent_nodes, node_name) without return types